Coated cathode active material for a battery cell

Abstract

A cathode active material for a battery cell is described. A protective layer is at least partially applied to the cathode active material, and the protective layer is made of a lithium ion-conducting solid electrolyte layer.

What is claimed is: 
     
       1. A cathode active material for a cathode of a lithium ion battery, the cathode active material being provided, at least in part, with a protective layer, wherein the protective layer is made of a lithium ion-conducting solid electrolyte layer that includes at least one of the following compounds:
 a) LiTiCoO 4  (lithium-titanium-cobalt oxide); and 
 b) argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I. 
 
     
     
       2. The cathode active material as recited in  claim 1 , wherein a thickness of the protective layer made of the lithium ion-conducting solid electrolyte is less than 15 nm. 
     
     
       3. The cathode active material as recited in  claim 1 , wherein the cathode active material includes a compound of formula LiMO 2 , where M is selected from Co, Ni, Mn or mixtures thereof or mixtures thereof with Al. 
     
     
       4. The cathode active material as recited in  claim 1 , wherein the cathode active material includes a compound of formula n LiNi 1−x M′ x O 2 ·(1−n) Li 2 MnO 3 , where M′ represents metal ions selected from Co, Mn, and mixtures thereof, 0<n<1, and 0<x<1. 
     
     
       5. A cathode for a lithium-ion battery, including at least one cathode active material, the cathode active material being provided, at least in part, with a protective layer, wherein the protective layer is made of a lithium ion-conducting solid electrolyte layer that includes at least one of the following compounds:
 a) LiTiCoO 4  (lithium-titanium-cobalt oxide); and 
 b) argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I. 
 
     
     
       6. A battery cell that includes at least one cathode, the cathode including at least one cathode active material, the cathode active material being provided, at least in part, with a protective layer, wherein the protective layer is made of a lithium ion-conducting solid electrolyte layer that includes at least one of the following compounds:
 a) LiTiCoO 4  (lithium-titanium-cobalt oxide); and 
 argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I. 
 
     
     
       7. A method for manufacturing an electrode of a battery cell, comprising:
 (i) providing a cathode active material; 
 (ii) at least partially coating the cathode active material with a protective layer, the protective layer being made of a lithium ion-conducting solid electrolyte that includes at least one of the following compounds: (a) LiTiCoO 4  (lithium-titanium-cobalt oxide); and (b) argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I; 
 (iii) assembling a current collector with a mixture produced in steps (i) and (ii). 
 
     
     
       8. The method as recited in  claim 7 , further comprising:
 (iv) adding a conductive additive to the cathode active material; 
 (v) adding a binder to the cathode active material; and 
 (vi) after the at least partially coating step, compacting the at least partially coated cathode active material. 
 
     
     
       9. The method as recited in  claim 7 , wherein for coating an active material, wherein the at least partially coating step is one of a physical method, a mechanical method, or a wet chemical method. 
     
     
       10. The method as recited in  claim 9 , wherein a thickness of the solid electrolyte layer is less than 15 nm. 
     
     
       11. The method as recited in  claim 8 , wherein the cathode active material is in the form of particles having a particle diameter in a range of ≥2 μm to ≤15 μm. 
     
     
       12. A method of using a solid electrolyte, the method comprising:
 coating at least a portion of a surface of a cathode active material of a cathode of a battery cell with a protective layer of the solid electrolyte, the solid electrolyte including at least one of the following compounds: (a) LiTiCoO 4  (lithium-titanium-cobalt oxide); and (b) argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I. 
 
     
     
       13. The cathode active material as recited in  claim 1 , wherein the lithium ion-conducting solid electrolyte layer of the protective layer includes the LiTiCoO 4  (lithium-titanium-cobalt oxide). 
     
     
       14. The cathode active material as recited in  claim 1 , wherein the lithium ion-conducting solid electrolyte layer of the protective layer includes the argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I. 
     
     
       15. The cathode as recited in  claim 5 , wherein the lithium ion-conducting solid electrolyte layer of the protective layer includes the LiTiCoO 4  (lithium-titanium-cobalt oxide). 
     
     
       16. The cathode as recited in  claim 5 , wherein the lithium ion-conducting solid electrolyte layer of the protective layer includes the argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I. 
     
     
       17. The battery cell as recited in  claim 6 , wherein the lithium ion-conducting solid electrolyte layer of the protective layer includes the LiTiCoO 4  (lithium-titanium-cobalt oxide). 
     
     
       18. The battery cell as recited in  claim 6 , wherein the lithium ion-conducting solid electrolyte layer of the protective layer includes the argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I. 
     
     
       19. The method as recited in  claim 7 , wherein the lithium ion-conducting solid electrolyte layer of the protective layer includes the LiTiCoO 4  (lithium-titanium-cobalt oxide). 
     
     
       20. The method as recited in  claim 7 , wherein the lithium ion-conducting solid electrolyte layer of the protective layer includes the argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I. 
     
     
       21. The method as recited in  claim 12 , wherein the solid electrolyte includes the LiTiCoO 4  (lithium-titanium-cobalt oxide). 
     
     
       22. The method as recited in  claim 12 , wherein the solid electrolyte includes the argyrodites of formula Li 6 PS 5 X, where X is selected from Cl, Br, and I.